[llvm] [TII] Split isTrivialReMaterializable into two versions [nfc] (PR #160377)

[Philip Reames via llvm-commits]

preames wrote:

Warning to anyone looking at this later, the landed version contained of https://github.com/llvm/llvm-project/pull/160319 contained a nasty bug where I'd accidentally reversed the condition being checked for.  This was (accidentally) undone in this review, so this ends up *not* being NFC as intended.  The final state is in line with the original intention of the two patches combined, so not going to revert.  It just makes the descriptions really dang confusing.  Sorry!

https://github.com/llvm/llvm-project/pull/160377